NEW YORK — When four film icons whose average age is a shade over 70 gather in a cavernous open studio for yet another chat about their new project, the potential for grumpiness is heartburn-inducing.

But Michael Douglas, 69, Robert De Niro, 70, Kevin Kline, 66, and Morgan Freeman, 76, have played the showbiz game a long time. And they seem to have genuinely enjoyed working together on Last Vegas, opening Friday, in which they play childhood buddies who head to the Nevada outpost for one last bachelor-party blowout.

They are relaxed and low-key, but each is more likely to let the other guy answer first before jumping in.

"Don't mix drinks," affirms Freeman. "Oh, you can't drink all the beer you want and all the whiskey you want. Don't mix the sugar. And drink lots of water before you go to bed. Hangovers are all about dehydration. I learned that long ago. So I can't even remember the last time I had a hangover. I can barely remember the last time I was drunk."

Jokes Douglas, "I bet you vaguely remember. I can tell you!"

Freeman assumes Douglas is referring to the night of the 2008 car crash in Mississippi that left his hand with nerve damage. "I wasn't drunk the night of this accident," Freeman says, pointing to his hand and the compression glove he's wearing. "I was not. Just to clear the air."

Douglas then gets back to the subject, saying he last had a hangover "a couple nights ago."

Neither has Douglas. "I've never been to one. I've never heard of one," he says. "It's like the girls having a bachelorette party?"

Kline is the only one who seems to have any experience in this area. "I went to one! We went to a strip club and had lunch and friends got lap dances. The look on somebody's face when someone's gyrating on them. What is that look? It's extra-terrestrial."

Now that the subject is lap dances, Freeman says he had one. "Once. In Paris. She was working her way through college. She was explaining to me as she danced. Very lovely. She was American."

Since the film is about old guys, grumpy or not, it's only fitting to ask how old they each feel. After all, Freeman's hand is a health issue that's been made public. As has Douglas' tongue cancer.

"I have no idea how old I feel!" barks Freeman. "I know how long I've been on the planet. I feel fine."

Throws in Douglas: "There's a lot of people who are dead that are younger than we are."

Then he admits, "I get up from sitting down here for awhile and I'm a little stiff.''

Kline: "You start making noises when you get in and out of cars. Argggh."

De Niro: "I make certain noises more than I used to."

Freeman: "I groan almost all the time."

Douglas: "I talk to myself."

Kline: "I whine a lot."

And then a serious Freeman adds, "Sometimes I'm just going 'uh, uh, uh.' I'm talking to the arm, because I'm in pain. Sometimes my arm feels like someone has a metal whip and is just squeezing it."

Do they think about getting old?

"Older? Absolutely,'' says Freeman. "I want to be here when the next lunar landing (occurs). I don't mean the next lunar landing, I mean the next Mars landing."

Kline: "I want to be part of the landing — when they're much faster. No jet lag."

De Niro: "How could you not (think about getting old)?" He says he often reads obituaries in the newspaper.

Why?

"I'm curious about what they've done,'' says De Niro. "It's a biography of their life."

Cracks Douglas: "He's not an obit pervert."

De Niro: "I look for the people I know and find them from time to time. Dennis Farina passed away (in July)."

Douglas: "He was 69."

De Niro: "I like to see what other people do and what they've been known for because there are professions I never even knew existed and then see what they passed away from. Heart condition. This. That. It's all interesting."

As for contemplating their own mortality, Douglas observes, "You always do in some way, but not really. It's gonna happen. You just try to prolong it as long as possible."

Since his cancer diagnosis in 2010, he says, "I'm very conscious of time now. I never was before. Now I kind of look chronologically and have to think about what else I want to do. I look at the years and I'm conscious of it. Just things I want to do and how much time do you actually have."

But he figures he's got genetics on his side. "I'm blessed my dad is 96, my mom is 90."

Freeman says it's about quality of life.

"I'm fighting anger inside myself because I can't live my life the way I was living it, to get in my airplane and fly to the Caribbean. Park the plane, get on my boat and sail away for six weeks. Can't do any of that. It pisses me off. Got to be careful not to be too pissed."

Kline: "Get someone else to fly you."

Morgan: "That's not what I want to do. I want to get in the plane and go off. I don't want to have to call somebody, even though I paid the guy."